The federal trial of a former state official from Quincy was watched closely by many public officials, including several high-ranking politicians on the South Shore, as the case cast a bright light on the practice of favoritism in government.

A jury on Thursday found John O’Brien, former commissioner of the state’s probation department, and two of his aides guilty of racketeering charges stemming from job-rigging allegations. The two-months-long trial exposed some hiring practices allegedly influenced by state leaders, including state Senate President Therese Murray, D-Plymouth.

Though Murray wasn’t charged with any crime, federal prosecutors said her office helped steer probation jobs as part of O’Brien’s patronage system.

“My office receives hundreds of requests for assistance for education, health care, housing, employment and more,” Murray said Thursday in a prepared statement released by her spokeswoman, Laura Oggeri. “As previously stated, I was unaware of any possible scheme or improper hiring practices at probation and, when I did learn what was going on, led a thorough overhaul of hiring at the department.

During trial, O’Brien’s defense attorney brought up the name of Norfolk County Sheriff Michael Bellotti of Quincy as an example that the type of patronage employed by O’Brien’s office was used in the state’s Trial Court system. The defense said Bellotti’s sister got the job as chief court officer at Dedham Superior Court after the sheriff put in a call to Murray’s office.

“This was a long and complicated trial,” Bellotti said in a prepared statement released by his spokesman, David Weber. “The number of questions asked by the jury during the testimony and during the deliberations phase of the trial bear that out.

“I didn’t have the benefit of being in the courtroom every day, and I’d want to take some time to digest all the information I can before commenting further.”